This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Young children with sickle cell disease (SCD) are at increased risk for neurodevelopmental deficits based on both disease specific and environmental risk factors such as lower socioeconomic status (Schatz et al., 2002;White et al., 2006). Despite these risks, there is insufficient understanding of the prevalence and nature of cognitive and developmental deficits in young children (less than 4 years of age) who have SCD. We are conducting a 4-year mixed cross-sectional longitudinal study of early neurodevelopmental status in children younger than 4 years with SCD. The study aims are to (1) characterize the prevalence and nature of the developmental deficits in infants and toddlers while controlling for SES;(2) examine the moderating effects of sickle cell phenotype, hematologic severity, and parent characteristics on developmental outcome;(3) improve patient outcomes by including routine parent education about normal development and behavior during each patient visit at the SCD Clinic. To accomplish these primary aims the study has two components: Neurodevelopmental Evaluation Component and Parent Education. The Neurodevelopmental Evaluation component, completed in the GCRC testing room, will determine the prevalence of developmental deficits among young children with SCD at specific age levels (9, 15, 21, 30, and 40 months). We plan a minimum of 45 assessments at each of the 5 age levels (225 assessments). The Parent Education component is a recurrent, SCD clinic-based intervention intended to impact patient outcomes.